anyone ever done 2 trye r 12s in tiburon need help

ok i got customer bringing it in on friday to have system removed from his ranger and installed in a tiburon.... well my delemia is he dont have time to bring it in to measure i have to build him a box so id like to build box before he brings the vehicles in so i can just install it

2 12inch type Rs
1400 watt kicker thats what he said it puts out not sure what model